Analysis of Coaxially Fed Microstrip Antennas of Arbitrary Shape with Thick Substrates

Publisher Website
Google Scholar
Abstract
Arbitrarily shaped, coax-fed microstrip patch antennas with substrates that may be electrically thick are studied using a mixed-potential integral equation approach. Vector basis functions defined over triangular elements are used to approximate the current distribution on the conducting patch. Rigorous and simplified models of the probe-to-patch junction, compatible with the triangular element model of the microstrip patch, are implemented and their relative merits are discussed. Two models of the coaxial probe, differing in accuracy and complexity, are also implemented and their ranges of validity are examined. Input impedance data for several microstrip patch antennas of different shapes, computed using different coax feed models, are presented and compared with measured results.